JP7445247B1 - Impurity removal unit and molten metal melting furnace, holding furnace or transfer trough equipped with an impurity removal unit - Google Patents

Abstract

An object of the present invention is to provide an impurity removal unit that can suppress the mixing of impurities into molten metal. An impurity removal unit (10) is surrounded by side walls (21, 31) and installed on bottom walls (20, 30) above which molten metal can move in one direction. The impurity removal unit 10 includes at least two barriers 11 arranged at intervals along the moving direction of the molten metal and blocks the movement of the molten metal, and includes at least two barriers 11 that block the movement of the molten metal. Among them, a first flow hole 12 through which the molten metal passes is formed in the lower part of the barrier 11A located on the most upstream side in the moving direction of the molten metal, and a first flow hole 12 through which the molten metal passes through the upper part of at least one other barrier 11B. A second communication hole 13 is formed. [Selection diagram] Figure 1

Description

The present invention relates to an impurity removal unit and a molten metal melting furnace, holding furnace or transfer trough equipped with an impurity removal unit.

For example, a melting and holding furnace consists of a melting chamber that melts metals such as aluminum and aluminum alloys, a holding chamber that receives the molten metal (so-called "molten metal") from the melting chamber and holds it at high temperature, and a pumping chamber that pumps out the molten metal. It is equipped with a private room. The holding chamber and the pumping chamber are arranged adjacent to each other and separated by a partition wall, and the molten metal is pumped out from the holding chamber through a communication section below the partition wall and above the bottom wall. It is possible to move to the room. The molten metal pumped out from the pumping chamber is used for casting, etc.

For example, foreign substances such as oxides and hard spots are present as impurities in the molten metal in the holding chamber. If impurities move with the molten metal from the holding chamber to the pumping chamber, the impurities will be mixed into the molten metal pumped out from the pumping chamber, and if the molten metal with impurities mixed in is used for casting, etc., it may cause defective products. Become. As described above, the quality of molten metal has an important effect on the quality of castings, etc., so it is necessary to take measures to prevent impurities from moving together with the molten metal from the holding chamber to the pumping chamber.

Patent Document 1 discloses that a step portion protruding upward from the holding chamber side bottom wall is formed at a connecting portion between the pumping chamber side bottom wall and the holding chamber side bottom wall below the partition wall, and the communicating portion is connected to the step portion. A melting and holding furnace is disclosed that is configured to open above the. In the melting and holding furnace of Patent Document 1, when the molten metal in the holding chamber moves to the pumping chamber, even if the precipitate in the holding chamber moves to the pumping chamber together with the molten metal, there is no space between the holding chamber and the pumping chamber. The movement of the precipitate is stopped at the stepped portion, and its movement to the pumping chamber is regulated. Thereby, the melting and holding furnace of Patent Document 1 suppresses impurities from being mixed into the molten metal in the pumping chamber.

JP 2019-109024 Publication

The impurities present in the holding chamber include not only precipitates that sink and accumulate on the bottom wall, but also suspended matter that floats on the surface of the molten metal. In the melting and holding furnace of Patent Document 1, although the movement of precipitates in the holding chamber to the pumping chamber can be sufficiently regulated, the movement of floating substances cannot be sufficiently regulated. For example, when the molten metal in the holding chamber is stirred for flux treatment, floating objects floating on the liquid surface of the molten metal may move below the partition wall and move from the communication portion to the pumping chamber. Or, when the molten metal in the pumping chamber is pumped out, the liquid level of the molten metal in the holding chamber falls, but at this time, floating objects floating on the liquid surface of the molten metal move below the partition wall. There is a risk that it may move from the communication part to the pumping room.

As described above, the melting and holding furnace of Patent Document 1 has a problem in that it cannot sufficiently suppress the mixing of impurities into the molten metal in the pumping chamber. This problem also occurs in a holding furnace that does not include a melting chamber.

The present invention has been made with an eye to solving the above problems, and an object of the present invention is to provide an impurity removal unit that can suppress the mixing of impurities into molten metal. Further, the present invention provides a melting and holding furnace or a holding furnace (hereinafter, in the present disclosure, a melting and holding furnace is also included in a holding furnace), which is equipped with an impurity removal unit to suppress impurities from entering the molten metal in the pumping chamber. (simply referred to as "holding furnace"). Another object of the present invention is to provide a melting furnace equipped with an impurity removal unit to prevent impurities from being mixed into the molten metal flowing out from the melting furnace. Another object of the present invention is to provide a transfer gutter equipped with an impurity removal unit for removing impurities mixed in molten metal distributed from a melting furnace or the like to various supply destinations.

In order to solve the above-mentioned problems, the subject of the present invention is an impurity removal unit described in Item 1 below.

Item 1. An impurity removal unit installed on a bottom wall surrounded by side walls and above which molten metal can move in one direction,
at least two barriers spaced apart along the direction of movement of the molten metal, including at least two barriers that block movement of the molten metal;
Of the at least two barriers, a first flow hole through which the molten metal passes is formed at the bottom of the barrier located most upstream in the direction of movement of the molten metal, and a first flow hole through which the molten metal passes is formed at the top of the other at least one barrier. , an impurity removal unit having a second flow hole through which the molten metal passes.

Further, the impurity removal unit of the present invention includes the impurity removal unit described in the following item 2 as a preferred embodiment of the impurity removal unit described in the above item 1.

Item 2. The impurity unit according to item 1,
a base placed on the bottom wall, on which the at least two barriers stand;
further comprising a pair of guides rising from the base and sandwiching the at least two barriers from both sides,
An impurity unit, wherein the base, the at least two barriers, and the pair of guides are integrated.

Further, the impurity unit of the present invention includes the impurity removal unit described in the following item 3 as a preferred embodiment of the impurity removal unit described in the above item 2.

Item 3. 3. The impurity unit according to item 2, wherein at least one of the pair of guides and/or the base is formed with an embedded part for embedding a heater.

Further, the impurity removal unit of the present invention includes the impurity removal unit described in the following item 4 as a preferred embodiment of the impurity removal unit described in the above item 2 or 3.

Item 4. comprising a gas introduction pipe into which an insoluble gas is introduced, and a degassing device including a bubble generator that generates bubbles of the insoluble gas;
4. The impurity unit according to item 2 or 3, wherein the gas introduction pipe extends along one of the pair of guides, and the bubble generator is attached to the base so as to release bubbles above the base.

Moreover, in order to solve the above-mentioned problem, the subject of the present invention is a holding furnace described in the following item 5.

Item 5. A holding furnace comprising at least a holding chamber for holding molten metal and a pumping chamber for pumping out the molten metal flowing from the holding chamber,
A holding furnace comprising the impurity removal unit according to any one of Items 1 to 4, which is installed on the bottom wall of the pumping chamber or the bottom wall of the holding chamber.

In the holding furnace according to item 5, it is preferable that the impurity removal unit is removably installed on the bottom wall of the pumping chamber or the bottom wall of the holding chamber; It may be integrated with the bottom wall of the holding chamber.

Moreover, in order to solve the above-mentioned problem, the subject of the present invention is a melting furnace described in the following item 6.

Item 6. A melting furnace equipped with a melting chamber for melting metal,
A melting furnace comprising the impurity removal unit according to any one of Items 1 to 4, which is installed on the bottom wall of the melting chamber.

In the melting furnace according to Item 6, the impurity removal unit is preferably removably installed on the bottom wall of the melting chamber, but may be integrated with the bottom wall of the melting chamber.

Moreover, in order to solve the above-mentioned problem, the subject of the present invention is a transfer gutter described in the following item 7.

Section 7. A transfer gutter for transferring molten metal,
A transfer gutter comprising the impurity removal unit according to any one of Items 1 to 4, which is installed on the bottom wall of the transfer gutter.

In the transfer gutter according to item 7, the impurity removal unit is preferably removably installed on the bottom wall of the transfer gutter, but may be integrated with the bottom wall of the transfer gutter.

According to the impurity removal unit of the present invention, impurities such as precipitates and floating substances mixed in molten metal can be effectively removed. Therefore, for example, in a holding furnace equipped with an impurity removal unit, it is possible to suppress impurities from entering the molten metal in the pumping chamber, and in a melting furnace equipped with an impurity removal unit, the molten metal flowing out from the melting furnace can be suppressed. It is possible to suppress the mixing of impurities, and in a transfer gutter equipped with an impurity removal unit, it is possible to suppress the mixing of impurities into the molten metal distributed from the melting furnace or the like to various supply destinations.

FIG. 1 shows a schematic configuration of a holding furnace. FIG. 2 shows a perspective view of the impurity removal unit. FIG. 3 shows a plan view of the impurity removal unit. FIG. 4 shows a perspective cross-sectional view taken along line AA in FIG. FIG. 5 shows a sectional perspective view taken along line BB in FIG.

The impurity removal unit of the present invention is for removing impurities mixed into molten metal from molten metal. Impurities include precipitates that settle to the bottom of the molten metal, as well as suspended matter that floats on the surface of the molten metal. In other words, the impurity removal unit of the present invention can effectively remove the precipitates that sink to the bottom of the molten metal and the floating substances that float on the liquid surface of the molten metal.

The impurity removal unit of the present invention can be used, for example, in a melting furnace that melts metals such as aluminum and aluminum alloys, in holding furnaces (including melting and holding furnaces) that hold molten metal at high temperatures, in melting furnaces, etc. It can be applied to transfer troughs that distribute metal to various supply destinations. In the melting furnace, it is possible to suppress impurities from being mixed into the molten metal flowing out from the melting furnace through the tap outlet. In the holding furnace, it is possible to suppress impurities from being mixed into the molten metal that flows from the holding chamber into the pumping chamber and is pumped out. The transfer gutter can prevent impurities from getting into the molten metal that is distributed from the melting furnace or the like to various supply destinations. The impurity removal unit of the present invention can be used in various machines, instruments, etc., in which molten metal exists in a recess surrounded by side walls on a bottom wall, and the molten metal can move in one direction above the bottom wall. Applicable to instruments, tools, etc.

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the following embodiments, an example will be shown in which the impurity removal unit of the present invention is applied to a holding furnace.

FIG. 1 shows a schematic configuration of a holding furnace 1 equipped with an impurity removal unit 10 of this embodiment. The holding furnace 1 includes at least a holding chamber 2 that holds molten metal such as aluminum or aluminum alloy at high temperature, and a pumping chamber 3 that pumps out the molten metal. Molten metal is supplied, for example, from a melting furnace via a transfer gutter. Alternatively, if the holding furnace 1 is a melting and holding furnace that further includes a melting chamber for melting metal, the molten metal is supplied to the holding chamber 2 from the melting chamber.

The holding chamber 2 has a container shape with an opening at the top, and includes a bottom wall 20 and a side wall 21 . The holding chamber 2 holds molten metal in a space surrounded by side walls 21 on a bottom wall 20 . A lid body 22 is removably provided at the upper part of the holding chamber 2. The upper opening of the holding chamber 2 is closed by a lid 22 so as to be openable and closable. A heater 4 such as a burner or a heater is attached to the lid body 22. The molten metal in the holding chamber 2 is heated by the heater 4 and held at a temperature higher than the melting temperature of the metal.

The pumping chamber 3 is arranged adjacent to the holding chamber 2. The pumping chamber 3 has a container shape with an opening at the top, and includes a bottom wall 30 and side walls 31. In this embodiment, the bottom wall 20 of the holding chamber 2 and the bottom wall 30 of the pumping chamber 3 are integrated, and the side wall 21 of the holding chamber 2 and the side wall 31 of the pumping chamber 3 are integrated. The holding chamber 2 and the pumping chamber 3 are separated by a partition wall 5. A molten metal communication section 50 is formed below the partition wall 5 and above the bottom walls 20 and 30, and the molten metal in the holding chamber 2 flows over the bottom wall 20 and below the partition wall 5. It is movable from the holding chamber 2 to the pumping chamber 3 (in the direction of arrow X in FIG. 1) through the communication portion 50. When the molten metal in the holding chamber 2 is stored in the pumping chamber 3, when the molten metal in the pumping chamber 3 is pumped out and the liquid level of the molten metal decreases, the molten metal in the holding chamber 2 is transferred to the pumping chamber 3. Moving.

The holding chamber 2 and the pumping chamber 3 (and the melting chamber) are formed by, for example, lining a casing made of metal such as steel with a refractory material. Note that a heat insulating material may be interposed between the casing and the refractory material, if necessary.

As shown in FIG. 1, the holding furnace 1 is designed to remove impurities in order to prevent impurities from entering the molten metal that flows from the holding chamber 2 into the pumping chamber 3 and is pumped out from the pumping chamber 3. A unit 10 is provided. The impurity removal unit 10 can be installed on the bottom wall 20 of the holding chamber 2. As a result, before flowing from the holding chamber 2 into the pumping chamber 3 through the communication section 50 below the partition wall 5, the molten metal flows in one direction (the pumping chamber 3 impurities mixed in the molten metal are removed from the molten metal by the impurity removal unit 10.

When the impurity removal unit 10 is installed on the bottom wall 20 of the holding chamber 2, it is preferable that the impurity removal unit 10 is placed in close contact with the partition wall 5. Since the communication part 50 below the partition wall 5 is the outlet of the molten metal in the holding chamber 2, when the impurity removal unit 10 is arranged closely to the partition wall 5, the molten metal flows from the holding chamber 2 into the pumping chamber 3. Impurities can be most effectively removed from molten metal. Note that the impurity removal unit 10 only needs to be close to the partition wall 5, and may be placed very close to the partition wall 5.

Alternatively, the impurity removal unit 10 can be installed on the bottom wall 30 of the pumping chamber 3. As a result, after the molten metal flows from the holding chamber 2 into the pumping chamber 3 through the communication section 50 below the partition wall 5, the molten metal flows in one direction (holding) above the bottom wall 30 in the pumping chamber 3. When the molten metal moves in the direction opposite to the chamber 2), impurities mixed in the molten metal are removed from the molten metal by the impurity removal unit 10.

The impurity removal unit 10 may be removably installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3, or may be installed on the bottom wall 20 of the holding chamber 2 or the bottom wall of the pumping chamber 3. It may be integrated with the wall 30. In this embodiment, the impurity removal unit 10 is removable from the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3. It is preferable that the impurity removal unit 10 is removable because, for example, when cleaning the holding furnace 1, the holding chamber 2 and the pumping chamber 3 can be easily cleaned, and the impurity removal unit 10 can also be easily cleaned and used again.

As shown in FIGS. 1 to 5, the impurity removal unit 10 includes at least two barriers 11 spaced apart along the direction of movement of molten metal. In this embodiment, the impurity removal unit 10 includes two barriers 11. Here, in the holding furnace 1, the molten metal moves from the holding chamber 2 to the pumping chamber 3, so the direction in which the holding chamber 2 and the pumping chamber 3 are lined up (the direction indicated by the arrow in FIG. direction).

The barrier 11 has a thick plate shape, and can be made of a fireproof material such as brick or cement. The barrier 11 has a rectangular shape in this embodiment. The height of the barrier 11 is higher than the highest liquid level of the molten metal when the barrier 11 is installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3. The upper end of the barrier 11 is designed so that it always protrudes from the liquid level. The length of the barrier 11 is such that when the barrier 11 is installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3, the length of the barrier 11 is between both longitudinal ends of the barrier 11 and the side wall 21 of the holding chamber 2. Alternatively, it is designed so that no gap is created between it and the side wall 31 of the pumping chamber 3. By designing the height and length of the barrier 11 as described above, the barrier 11 basically blocks the movement of molten metal, that is, the first flow hole 12 and the second flow hole 13 which will be described later. It is installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3 so as to block the movement of molten metal in other parts. The thickness of the barrier 11 is determined so that when the barrier 11 is installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3, the barrier 11 will not be easily damaged or deformed due to movement of molten metal. It is designed to have.

Of the at least two barriers 11, the barrier 11A located most upstream in the moving direction of the molten metal has a first flow hole 12 formed in its lower part. The lower part of the barrier 11A is a portion below 1/2 of the height of the barrier 11A. The first flow hole 12 is designed to minimize the amount of molten metal that accumulates in the holding chamber 2 and pumping chamber 3 of the holding furnace 1 where the impurity removal unit 10 is installed, as well as in the melting chamber and transfer gutter of the melting furnace. It is located far below the liquid level (hereinafter referred to as the "lowest liquid level of molten metal") when the metal is molten metal. The first flow hole 12 penetrates the barrier 11A in the thickness direction and allows molten metal to move from one side of the barrier 11A to the other side. The shape and size of the first flow hole 12 are not particularly limited, and can be designed to have an appropriate shape and size that allow smooth movement of molten metal. For example, the shape of the first communication hole 12 can be a horizontally long rectangle when viewed in cross section, and the size of the first communication hole 12 can be 50 mm in length and 100 mm in width.

Since the first flow hole 12 is formed at the lower part of the barrier 11A, even if the molten metal passes through the first flow hole 12 and passes through the barrier 11A, floating objects F floating on the liquid surface of the molten metal will not reach the barrier 11A. When they collide, they cannot pass through the barrier 11A, and the floating matter F is prevented from moving together with the molten metal. As a result, it is possible to avoid as much as possible the floating matter F, among the impurities mixed in the molten metal, from moving from the holding chamber 2 to the pumping chamber 3 and being present in the molten metal in the pumping chamber 3. Therefore, it is possible to suppress the floating matter F from being mixed into the molten metal pumped out from the pumping chamber 3.

The position of the upper end of the first flow hole 12 is preferably 50 mm or more and 200 mm or less below the position of the lowest liquid level of the molten metal. As a result, even if floating objects F floating on the liquid surface of the molten metal move somewhat downward along the barrier 11A as the molten metal moves, the floating objects F will not pass through the barrier 11A from the first flow hole 12. can be effectively suppressed. Further, the lower end of the first flow hole 12 may be located on the top surface of the bottom walls 20, 30 of the holding furnace 1, where the impurity removal unit 10 is installed, or on the bottom wall of the melting chamber of the melting furnace or the transfer gutter, for example. It is preferable that the distance is 50 mm or more and 100 mm or less upward from the position of the upper surface (hereinafter referred to as "the bottom wall on which the impurity removal unit 10 is installed"). This can also reduce the possibility that the precipitate P that settles below the molten metal will pass through the barrier 11A from the first flow hole 12 as the molten metal moves.

A second communication hole 13 is formed in the upper part of at least one other barrier 11B among the at least two barriers 11. The upper part of the barrier 11B is a portion above 1/2 of the height of the barrier 11B. The second flow hole 13 is located above the first flow hole 12 and is located on the top surface of the bottom wall where the impurity removal unit 10 is installed, or on the top surface of the base 14 when the impurity removal unit 10 includes the base 14. It is located far above and above the position. The second flow hole 13 penetrates the barrier 11B in the thickness direction and allows molten metal to move from one side of the barrier 11B to the other side. The shape and size of the second flow hole 13 are not particularly limited, and can be designed to have an appropriate shape and size that allow smooth movement of molten metal. For example, the shape of the second communication hole 13 can be a horizontally long rectangle when viewed in cross section, and the size of the second communication hole 13 can be 50 mm in length and 100 mm in width.

Since the second flow hole 13 is formed in the upper part of the barrier 11B, even if the molten metal passes through the second flow hole 13 and passes through the barrier 11A, it will not settle at the lower part of the molten metal (near the bottom walls 20 and 30). The precipitate P hits the barrier 11B and cannot pass through the barrier 11B, thereby preventing the precipitate P from moving together with the molten metal. This makes it possible to prevent the precipitate P from moving from the holding chamber 2 to the pumping chamber 3 and being present in the molten metal in the pumping chamber 3 among the impurities mixed in the molten metal. Therefore, it is possible to suppress the precipitate P from being mixed into the molten metal pumped out from the pumping chamber 3.

The position of the lower end of the second communication hole 13 is preferably 200 mm or more and 600 mm or less above the upper surface of the bottom wall on which the impurity removal unit 10 is installed or the upper surface of the base 14 . As a result, even if the precipitate P that settles at the bottom of the molten metal moves somewhat upward along the barrier 11B as the molten metal moves, it is effectively prevented from passing through the barrier 11B from the second flow hole 13. can. In addition, when the barrier 11B in which the second communication hole 13 is formed is arranged closely to the partition wall 5, the second communication hole 13 is formed below the lower end of the partition wall 5. Further, the position of the upper end of the second flow hole 13 is preferably 50 mm or more and 100 mm or less below the position of the lowest liquid level of the molten metal. As a result, even if floating objects F are mixed into the molten metal that has passed through the barrier 11A, the floating objects F floating on the surface of the molten metal will move from the second flow hole 13 to the barrier as the molten metal moves. 11B can be suppressed.

It is preferable that the impurity removal unit 10 includes at least two barriers 11 and a base 14 on which the barriers 11 stand. The base 14 has a thick plate shape and can be made of a fireproof material such as brick or cement. The base 14 is integrated with at least two barriers 11. The base 14 is placed on the bottom wall 20 of the holding chamber 2 or on the bottom wall 30 of the pumping chamber 3. Thereby, at least two barriers 11 can be easily installed on the bottom wall 20 of the holding chamber 2 or on the bottom wall 30 of the pumping chamber 3.

The base 14 has a rectangular shape in this embodiment. The thickness of the base 14 is designed to have enough strength to prevent the base 14 from being easily damaged or deformed. The length of the base 14 is determined by the distance between both longitudinal ends of the base 11 and the side wall 20 of the holding chamber 2 when the base 14 is installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3. Alternatively, it is designed so that no gap is created between it and the side wall 31 of the pumping chamber 3. The width of the base 14 is designed so that all the barriers 11 can be integrated on its upper surface.

It is preferable that the impurity removal unit 10 includes, in addition to at least two barriers 11, a pair of guides 15 that sandwich the at least two barriers 11 from both sides. The guide 15 has a thick plate shape, and can be made of a fireproof material such as brick or cement. A pair of guides 15 are integrated with at least two barriers 11. In this embodiment, the pair of guides 15 rise from the base 14 and are integrated with the base 14.

When installing at least two barriers 11 on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3, the pair of guides 15 are connected to the side wall 21 of the holding chamber 2 or the side wall 31 of the pumping chamber 3. Contact. As a result, when the at least two barriers 11 are inserted into the holding chamber 2 or the pumping chamber 3 and installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3, the pair of guides 15 slides on the side wall 21 of the holding chamber 2 or the side wall 31 of the pumping chamber 3, so that at least two barriers 11 can be easily inserted into the holding chamber 2 or into the pumping chamber 3. In addition, when at least two barriers 11 are installed on the bottom wall 20 of the holding chamber 2 or on the bottom wall 30 of the pumping chamber 3, the pair of guides 15 are connected to the side wall 21 of the holding chamber 2 or the side wall 30 of the pumping chamber 3. Therefore, it is possible to prevent a gap from being formed between both longitudinal ends of the barrier 11 and the side wall 21 of the holding chamber 2 or the side wall 31 of the pumping chamber 3.

In this embodiment, the guide 15 has a rectangular shape in plan view. The thickness of the guide 15 is designed to have enough strength to prevent the guide 15 from being easily damaged or deformed. The width of the base 15 is designed so that all the barriers 11 can be integrated. The height of the guide 15 is greater than the highest liquid level height of the molten metal when the barrier 11 is installed on the bottom wall 20 of the holding chamber 2 or on the bottom wall 30 of the pumping chamber 3, that is, the height of the molten metal is The upper end of the guide 15 is designed to always protrude from the liquid level. In this embodiment, the height of the guide 15 and the height of the barrier 11 match.

The impurity removal unit 10 of this embodiment includes two barriers 11, a base 14, and a pair of guides 15. It has a box shape with an open top, forming a pair of opposing sides. Thereby, the impurity removal unit 10 can be easily installed on the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3 by submerging the impurity removal unit 10 in the molten metal.

In the impurity removal unit 10, it is preferable that an embedded part 16 for embedding a heater is formed in at least one of the pair of guides 15 and/or the base 14. The embedded portion 16 is a cavity formed in the guide 15 or the base 14, and by embedding a heater therein, the molten metal can be indirectly heated. This makes it possible to suppress a drop in the temperature of the molten metal, so that the molten metal maintained at a high temperature can be pumped out from the pumping chamber 3. The heater is not particularly limited as long as it can be embedded in the embedded portion 16.

The embedded portion 16 is preferably formed in at least one of the pair of guides 15, and the upper end of the embedded portion 16 is preferably open at the upper surface of the guide 15. Thereby, the heater can be easily embedded in the guide 15. Moreover, it is preferable that the embedded part 16 is L-shaped and extends from the guide 15 to the base 14. Thereby, the heater can be easily embedded in the base 14.

It is preferable that the impurity removal unit 10 includes a degassing device 17. The degassing device 17 includes a gas introduction pipe 18 into which an inert gas is introduced, and a bubble generator 19 which generates inert gas bubbles.

The gas introduction pipe 18 is formed in a pipe shape with openings at both ends, and extends vertically along one of the pair of guides 15. One end of the gas introduction pipe 18 is connected to the bubble generator 19, and the other end of the gas introduction pipe 18 projects above the guide 15 and is connected to a gas supply pipe extending from an inert gas supply source. This concept includes insoluble gases, gases that do not dissolve in molten metal, and gases that are difficult to dissolve in molten metal. As the insoluble gas, for example, an inert gas such as argon, or a gas such as nitrogen or chlorine can be used. The gas introduction pipe 18 is, for example, a pipe body made of metal such as steel, stainless steel, or cast iron, and covered with a porous refractory material.

The bubble generator 19 has a hollow box shape, and for example, in this embodiment, it has a rectangular shape in plan view. The bubble generator 19 is attached to the base 14 so as to emit bubbles above the base 14. The bubble generator 19 has, for example, an internal space and a main body made of the same metal as the gas introduction pipe 18 and covered with a porous refractory material. One end of the gas introduction pipe 18 is connected to one end of the bubble generator 19, and insoluble gas is introduced into the bubble generator 19.

A discharge portion 190 is formed at the other end of the bubble generator 19 to form bubbles of the insoluble gas introduced into the bubble generator 19 and release them above the base 14 . The discharge part 190 is constituted by, for example, a plurality of gas flow holes formed in the upper surface of a metal main body part constituting the bubble generator 19, and a large number of pores included in a porous refractory material. The insoluble gas introduced into the bubble generator 19 passes through the pores of the porous refractory material through the gas flow holes, and is fragmented at that time to become fine bubbles, which are released above the base 14. be done. Gas such as hydrogen dissolved in the molten metal is captured by fine bubbles of insoluble gas rising in the molten metal and released from the molten metal to the outside.

Although the bubble generator 19 is embedded in the base 14, it may be installed on the base 14. Although the gas introduction pipe 18 is installed inside the guide 15, a part or all of it may be embedded in the guide 15.

The degassing device 17 is not limited to the configuration of this embodiment described above, and any known degassing device can be used.

The impurity removal unit 10 of the present embodiment described above includes at least two barriers 11 arranged at intervals along the moving direction of the molten metal, and includes at least two barriers 11 that block the movement of the molten metal. Of the at least two barriers 11, a first flow hole 12 through which the molten metal passes is formed in the lower part of the barrier 11A located on the most upstream side in the direction of movement of the molten metal, and at least one other barrier 11B. A second flow hole 13 through which molten metal passes is formed in the upper part of the hole. As a result, according to the impurity removal unit 10 of the present embodiment, even if the molten metal contains precipitates P and floating substances F as impurities, when the molten metal passes through the first flow hole 12 at the lower part of the barrier 11A. In this case, the floating matter F is prevented from moving together with the molten metal by the barrier 11A, and when the molten metal passes through the second flow hole 13 at the upper part of the barrier 11B, the precipitate P is prevented from moving together with the molten metal. The movement of the molten metal effectively removes impurities from the molten metal as it is restricted by the barrier 11B.

Therefore, by applying the impurity removal unit 10 to the holding furnace 1, it is possible to suppress the precipitate P from being mixed into the molten metal that flows into the pumping chamber 3 from the holding chamber 2 and is pumped out from the pumping chamber 3. Therefore, clean (high quality) molten metal with no or very few impurities can be used for casting.

Further, the impurity removal unit 10 of this embodiment has a box shape in which at least two barriers 22, a base 14, and a pair of guides 15 are integrated. Therefore, according to the impurity removal unit 10 of this embodiment, the impurity removal unit 10 can be easily installed in the holding furnace 1. Furthermore, the impurity removal unit 10 can be easily removed from the holding furnace 1, and the holding furnace 1 and the impurity removal unit 10 can be easily cleaned, and the impurity removal unit 10 can be used again.

Further, in the impurity removal unit 10 of this embodiment, an embedded part 17 for embedding a heater is formed in at least one of the pair of guides 15 and/or the base 14. Therefore, according to the impurity removal unit 10 of this embodiment, it is possible to suppress the temperature drop of the molten metal.

Further, the impurity removal unit 10 of this embodiment includes a degassing device 17 including a gas introduction pipe 18 into which an insoluble gas is introduced and a bubble generator 19 that generates bubbles of the insoluble gas, and a pair of gas introduction pipes 18 are provided. The air bubble generator 19 is attached to the base 14 so as to emit air bubbles above the base 14. Therefore, according to the impurity removal unit 10 of the present embodiment, gas such as hydrogen dissolved in the molten metal can be removed from the molten metal using bubbles.

Although one embodiment of the present invention has been described above, the embodiment described above is merely an example and is not restrictive. Therefore, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

For example, in the embodiment described above, the impurity removal unit 10 includes two barriers 11. In contrast, as a modification, the impurity removal unit 10 may include three or more barriers 11. When the impurity removal unit 10 includes three or more barriers 11, one of the first flow hole 12 and the second flow hole 13 is formed as the third and subsequent barriers. For example, when the impurity removal unit 10 includes four barriers 11, the barrier 11A on the most upstream side in the direction of movement of molten metal is formed with the first communication hole 12, and the barrier 11B on the downstream side is formed with the second communication hole 13. A first flow hole 12 is formed in the barrier 11 located further downstream, and a second flow hole 13 is formed in the barrier 11 further downstream. In this way, by forming the first flow holes 12 and the second flow holes 13 alternately in the plurality of barriers 11 lined up from the upstream side to the downstream side in the moving direction of the molten metal, floating particles F are prevented from flowing into the molten metal. Also, contamination of impurities in the precipitate P can be effectively suppressed. Note that it is not necessarily necessary to form the first flow holes 12 and the second flow holes 13 alternately in the plurality of barriers 11, and the first flow holes 12 and the second flow holes 13 are not necessarily formed in the barrier 11A located furthest upstream in the direction of movement of the molten metal. 12 and the second communication hole 13 is formed in at least one other barrier 11B, the first communication hole 12 or the second communication hole 13 can be formed freely.

For example, in the embodiment described above, the impurity removal unit 10 includes a pair of guides 15 . On the other hand, as a modification, the impurity removal unit 10 may not include the pair of guides 15 and may have a form in which at least two barriers 11 are integrated into the base 14.

For example, in the embodiments described above, impurity removal unit 10 includes base 14 . On the other hand, as a modification, the impurity removal unit 10 may not include the base 14 and may have a configuration in which at least two barriers 11 are integrated with a pair of guides 15.

For example, in the embodiment described above, the impurity removal unit 10 includes a base 14 and a pair of guides 15. On the other hand, as a modification, the impurity removal unit 10 may not include the base 14 and the pair of guides 15, and may be configured only with at least two barriers 11. In this case, the impurity removal unit 10 (at least two barriers 11) is integrated into the bottom wall 20 of the holding chamber 2 or the bottom wall 30 of the pumping chamber 3.

For example, in the embodiment described above, an embedded portion 16 for embedding a heater is formed in the guide 15 and base 14 of the impurity removal unit 10. On the other hand, as a modified example, the molten metal can be directly heated by, for example, immersing an immersion heater or an immersion heater into the molten metal without forming the embedded part 16 in the guide 15 or base 14 of the impurity removal unit 10. It's okay. Alternatively, it is not necessary to heat the molten metal with a heater or the like in the impurity removal unit 10.

For example, in the embodiment described above, the impurity removal unit 10 includes the degassing device 17. On the other hand, as a modification, the impurity removal unit 10 may not include the degassing device 17, and the impurity removal unit 10 may not remove gas such as hydrogen contained in the molten metal.

For example, in the embodiment described above, the impurity removal unit 10 is applied to the holding furnace 1. On the other hand, as a modification, the impurity removal unit 10 may be applied to a melting furnace. The melting furnace includes at least a melting chamber for melting metal, and the molten metal generated by melting the metal in the melting chamber flows out from the tap. By installing the impurity removal unit 10 on the bottom wall of the melting chamber, impurities such as precipitates P and floating materials F mixed in the molten metal are removed by the impurity removal unit 10 while the molten metal moves to the tap outlet. . Therefore, it is possible to suppress impurities from being mixed into the molten metal flowing out from the melting furnace. It is preferable that the impurity removal unit 10 is installed on the bottom wall of the melting chamber at a position close to the tap outlet.

Note that the melting chamber has a structure that includes a melting section that melts the metal, and a tapping section that is equipped with a tapping port, receives molten metal from the melting section, temporarily holds the molten metal, and then drains it from the tap. It may be. In this case, the impurity removal unit 10 is preferably installed at a position close to the tap on the bottom wall of the tap of the melting chamber.

As another variant, the impurity removal unit 10 may be applied to a transfer trough. The transfer gutter is formed in a concave shape when viewed in cross section, and transfers, for example, molten metal flowing out from a melting furnace and distributes the metal to various supply destinations. By installing the impurity removal unit 10 on the bottom wall of the transfer gutter, the impurities such as sediment P and suspended matter F mixed in the molten metal are removed by the impurity removal unit 10 while the molten metal is being transferred to various supply destinations. be done. Therefore, it is possible to suppress impurities from being mixed into the molten metal distributed from the melting furnace or the like to various supply destinations.

1 Holding furnace 2 Processing tank 3 Electrolyzer 10 Impurity removal unit 11 Barrier 11A Barrier located at the most upstream side in the moving direction of molten metal of at least two barriers 11B At least one other barrier of at least two barriers 12 First Distribution hole 13 Second distribution hole 14 Base 15 Guide 16 Embedded part 17 Degassing device

Claims (7)

An impurity removal unit installed on a bottom wall surrounded by side walls and over which molten metal containing melted aluminum and/or aluminum alloy can move in one direction,
at least two barriers spaced apart along the direction of movement of the molten metal, including at least two barriers that block movement of the molten metal;
an upper portion between the at least two barriers is open;
Of the at least two barriers, a first barrier through which the molten metal passes is formed at a lower part of the first barrier located on the most upstream side in the direction of movement of the molten metal, and a first flow hole through which the molten metal passes is formed. A second flow hole through which the molten metal passes is formed in the upper part of the second barrier,
The position of the lower end of the first communication hole is upwardly away from the position of the upper surface of the bottom wall,
The second communication hole is formed above 1/2 of the height of the second barrier, and the position of the upper end of the second flow hole is the position of the upper end of the second barrier. The impurity removal unit is spaced downward from the . The impurity unit according to claim 1,
a base placed on the bottom wall, on which the at least two barriers stand;
further comprising a pair of guides rising from the base and sandwiching the at least two barriers from both sides,
An impurity unit, wherein the base, the at least two barriers, and the pair of guides are integrated. The impurity unit according to claim 2, wherein at least one of the pair of guides and/or the base is formed with an embedded part for embedding a heater. A degassing device including a gas introduction pipe into which an insoluble gas is introduced and a bubble generator that generates bubbles of the insoluble gas,
3. The impurity unit of claim 2, wherein the gas inlet tube extends along one of the pair of guides and the bubble generator is attached to the base so as to emit bubbles above the base. A holding furnace comprising at least a holding chamber for holding molten metal and a pumping chamber for pumping out the molten metal flowing from the holding chamber,
A holding furnace comprising the impurity removal unit according to any one of claims 1 to 4, which is installed on the bottom wall of the pumping chamber or the bottom wall of the holding chamber. A melting furnace equipped with a melting chamber for melting metal,
A melting furnace comprising the impurity removal unit according to any one of claims 1 to 4 installed on the bottom wall of the melting chamber. A transfer gutter for transferring molten metal,
A transfer gutter comprising an impurity removal unit according to any one of claims 1 to 4 installed on the bottom wall of the transfer gutter.

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