Circulating non-iron metal melting furnace

Abstract

The structure is simplified, and the molten metal flows more smoothly, allowing for efficient dissolution and heating. [Solution] The furnace body 10 has heating chambers 12 and 13 that communicate with an input port 11 for non-ferrous metal materials, and a tapping chamber 14 that can receive a portion of the molten metal heated to a predetermined temperature in the heating chambers 12 and 13 and from which the molten metal can be removed, and a rotating blade 20 for circulation that is provided in the center of the heating chambers 12 and 13 to circulate the molten metal, and a plurality of electric heaters 30 and 40 provided in the heating chambers 12 and 13 to raise the molten metal to a predetermined temperature.

Description

Technical Field

[0001] The present invention relates to a circulating non-ferrous metal melting furnace that melts non-ferrous metals such as aluminum alloys while circulating them for the purpose of using them in the production of various cast products such as die-casting.

Background Art

[0002] Conventionally, for melting non-ferrous metals such as aluminum alloys, melting furnaces using radiant flames from gas burners using fossil fuels such as petroleum have been mainly adopted. However, since radiant flames from gas burners using fossil fuels have problems in terms of thermal efficiency and the environment, improvement measures have been demanded.

[0003] As an improvement measure, a non-ferrous metal melting furnace having a structure in which an electric heater is immersed in molten metal has been disclosed (see, for example, Patent Document 1). As shown in FIG. 3, the non-ferrous metal melting furnace 50 described in this Patent Document 1 is provided with a plurality of chambers including a melting chamber 51, a heating chamber 52, and a dross removal chamber 53. The non-ferrous metal material charged into the melting chamber 50 is melted by an electric heater 56 provided in the heating chamber 5z and heated to a predetermined temperature, and then supplied from there to a tapping chamber by way of a calming chamber 54. The molten metal circulates from the dross removal chamber 53 to the heating chamber 52, but no electric heater is provided in this dross removal chamber 53.

[0004] Since this non-ferrous metal melting furnace 50 uses an electric heater to melt and heat the non-ferrous metal material, it has a great advantage of being superior in terms of thermal efficiency and the environment compared to the conventional melting furnace using a gas burner.

[0005] However, the inventors of the present invention have not been satisfied with such a situation and have further advanced research and development, and have developed a circulating non-ferrous metal melting furnace that can melt and heat non-ferrous metal materials more efficiently with a novel configuration that has not existed until now (Patent Document 2).

[0006] As shown in Figure 4, this circulating non-ferrous metal melting furnace 101 has a furnace body 110 that includes an inlet 111 for non-ferrous metal materials, a first heating chamber 112 communicating with the inlet 111, a second heating chamber 113 arranged parallel to the first heating chamber 112 via an intermediate wall 115 and forming a circulation path for the molten metal to circulate between the first heating chamber 112 and the second heating chamber 113, and a tapping chamber 114 that communicates with the downstream side of the first heating chamber 112 and can receive a portion of the molten metal heated to a predetermined temperature in the first heating chamber 112 and from which the molten metal can be removed. The system includes a circulation pump 120 for circulating the molten metal, a plurality of first electric heaters 130 installed in the first heating chamber 112 to raise the molten metal to a predetermined first temperature, and a plurality of second electric heaters 140 installed in the second heating chamber 113 to raise the molten metal, which has been heated to the first temperature in the first heating chamber 112, to a second temperature exceeding the first temperature. The molten metal, which has been heated to the second temperature in the second heating chamber 113, is circulated back to the first heating chamber 112, and its heat is transferred to the non-ferrous metal material introduced from the inlet 111. A partition wall 117 is provided between the first heating chamber 112 and the molten metal outlet chamber 114. A connecting passage 117a is formed in this partition wall 117, connecting the first heating chamber 112 to the molten metal outlet chamber 114. The molten metal outlet chamber 114 is equipped with a mechanism (not shown) for removing the received molten metal to the outside.

[0007] According to this, molten metal is circulated by a circulation pump 120 through a circulation path formed by the first heating chamber 112 and the second heating chamber 113. A portion of the molten metal, which has been heated to a predetermined temperature (first temperature) in the first heating chamber 112 by the first electric heater 130, is received in the tapping chamber 114. Furthermore, the molten metal from the first heating chamber 112 is heated to a temperature exceeding the predetermined temperature (second temperature) in the second heating chamber 113 by the second electric heater 140, and then circulated back to the first heating chamber 112. This allows non-ferrous metal material introduced into the first heating chamber 112 from the input port 111 to be effectively melted and heated.

[0008] However, the circulating non-ferrous metal melting furnace 101 shown in Figure 4 is provided with an intermediate wall 115 to ensure a circulation path for the molten metal. Adding an intermediate wall 115 would complicate the structure, increase costs, and potentially create obstacles during maintenance. Furthermore, if the molten metal flows into each of the four corners, vortices may form there, which can prevent a smooth flow from being achieved. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2010-96401 [Patent Document 2] Patent No. 6997738 [Patent Document 3] Patent No. 4183732 [Patent Document 4] Patent No. 6572325 [Overview of the project] [Problems that the invention aims to solve]

[0010] Therefore, the object of the present invention is to provide a circulating non-ferrous metal melting furnace that simplifies the structure and allows for a smoother flow of molten metal, enabling efficient melting and heating. [Means for solving the problem]

[0011] To achieve the above objective, the circulating non-ferrous metal melting furnace of the present invention is a circulating non-ferrous metal melting furnace (1) that melts non-ferrous metal materials using an immersion electric heater, A furnace body (10) having an inlet (11) for non-ferrous metal material, heating chambers (12, 13) communicating with the inlet (11), and a tapping chamber (14) communicating with the heating chambers (12, 13) that can receive a portion of the molten metal heated to a predetermined temperature in the heating chambers (12, 13) and from which the molten metal can be removed, A rotating vane (20) for circulating molten metal is provided in the center of the aforementioned heating chamber (12,13), The heating chamber (12, 13) is provided with a plurality of electric heaters (30, 40) for raising the temperature of the molten metal to a predetermined temperature.

[0012] Furthermore, the present invention comprises a first heating chamber (12) located in the flow path from the inlet (11) to the outlet chamber (14) on the right half side around the rotating blade (20), and a second heating chamber (13) located in the flow path from the outlet chamber (14) to the inlet (11) on the left half side around the rotating blade (20), The electric heaters consist of a plurality of first electric heaters (30) provided in the first heating chamber (12) to raise the molten metal to a predetermined first temperature, and a plurality of second electric heaters (40) provided in the second heating chamber (13) to raise the molten metal, which has been heated to the first temperature in the first heating chamber (12), to a second temperature exceeding the first temperature. The molten metal, heated to the second temperature in the second heating chamber (13), is circulated to the first heating chamber (12) to transfer its heat to the non-ferrous metal material introduced through the inlet (11).

[0013] Furthermore, the circulating non-ferrous metal melting furnace of the present invention is a circulating non-ferrous metal melting furnace (1) that melts non-ferrous metal materials using an immersion electric heater, The furnace body (10) has an inlet (11) for non-ferrous metal material, heating chambers (12, 13) communicating with the inlet (11), and a tapping chamber (14) communicating with the heating chambers (12, 13) that can receive a portion of the molten metal heated to a predetermined temperature in the heating chambers (12, 13) and from which the molten metal can be removed, and has a space (60) in the center and is donut-shaped in plan view. A circulation pump (70) is provided in the heating chamber (12) for circulating the molten metal, The heating chamber (12, 13) is provided with a plurality of electric heaters (30, 40) for raising the temperature of the molten metal to a predetermined temperature.

[0014] Further, in the present invention, the heating chambers (12, 13) include a first heating chamber (12) provided in a flow path that extends from the charging port (11) side to the hot water outlet chamber (14) side on the right half side around the space (60), and a second heating chamber (13) provided in a flow path that extends from the hot water outlet chamber (14) side to the charging port (11) side on the left half side around the space (60). A plurality of electric heaters are provided in the first heating chamber (12), including a first electric heater (30) for heating the molten metal to a predetermined first temperature, and a plurality of electric heaters are provided in the second heating chamber (13) for heating the molten metal heated to the first temperature in the first heating chamber (12) to a second temperature exceeding the first temperature; the second electric heater (40). The molten metal heated to the second temperature in the second heating chamber (13) is circulated to the first heating chamber (12) so as to supply its heat to the non-ferrous metal material charged from the charging port (11).

[0015] Further, in the present invention, the non-ferrous metal material is aluminum or an aluminum alloy.

[0016] The symbols in the parentheses above indicate corresponding elements or corresponding matters described in the drawings and the embodiments for carrying out the invention described later.

Advantages of the Invention

[0017] According to the present invention, in a circulation-type non-ferrous metal melting furnace that melts a non-ferrous metal material using an electric heater, a rotating blade for circulation that circulates the molten metal is provided at the center of the heating chamber. Therefore, the molten metal rotates in a circular motion while being divided into a flow path that flows from the charging port side to the hot water outlet chamber side on the right half side and a flow path that flows from the hot water outlet chamber side to the charging port side on the left half side around the rotating blade. According to this, as shown in the conventional example, there is no need to provide an intermediate wall in the furnace body, and it is only necessary to provide a rotating blade. Therefore, the structure of the circulation-type non-ferrous metal melting furnace can be simplified, and the cost is not particularly high. In addition, by making the molten metal flow in a circular motion, a circulating non-ferrous metal melting furnace can be obtained that makes the molten metal flow more smoothly and can efficiently melt and raise the temperature.

[0018] According to the present invention, the heating chamber is composed of a first heating chamber provided in a flow path from the charging port side to the tapping chamber side on the right half side around the rotating blade, and a second heating chamber provided in a flow path from the tapping chamber side to the charging port side on the left half side around the rotating blade. A first electric heater for raising the temperature to a predetermined first temperature is provided in each of the first heating chamber and the second heating chamber, and a second electric heater for raising the temperature to a second temperature exceeding the first temperature is provided. The molten metal heated to the second temperature in the second heating chamber is circulated to the first heating chamber, and its heat is applied to the non-ferrous metal material charged from the charging port. Therefore, the non-ferrous metal material can be efficiently melted and heated in a short time.

[0019] According to the present invention, in a circulating non-ferrous metal melting furnace that uses an electric heater to melt a non-ferrous metal material, a space is provided in the central part of the furnace body itself, and the shape is a donut shape in plan view. A circulation pump for circulating the molten metal is provided in the heating chamber, and a plurality of electric heaters for raising the temperature of the molten metal to a predetermined temperature are provided. By making the flow of the molten metal in a circular motion, the molten metal can flow more smoothly and can be efficiently melted and heated. According to this, as shown in the conventional example, there is no need to provide an intermediate wall in the furnace body, and it is only necessary to make the shape of the furnace body itself a donut shape in plan view. Therefore, the structure of the circulating non-ferrous metal melting furnace can be simplified, and in particular, the cost will not increase significantly.

[0020] According to the present invention, the heating chamber is composed of a first heating chamber provided in a flow path from the charging port side to the tapping chamber side on the right half side around the space, and a second heating chamber provided in a flow path from the tapping chamber side to the charging port side on the left half side around the space. A first electric heater for raising the temperature to a predetermined first temperature is provided in each of the first heating chamber and the second heating chamber, and a second electric heater for raising the temperature to a second temperature exceeding the first temperature is provided. The molten metal heated to the second temperature in the second heating chamber is circulated to the first heating chamber, and its heat is applied to the non-ferrous metal material charged from the charging port. Therefore, the non-ferrous metal material can be efficiently melted and heated in a short time.

[0021] Furthermore, according to the present invention, since the non-ferrous metal material is aluminum or an aluminum alloy, various cast products using aluminum can be manufactured successfully. [Brief explanation of the drawing]

[0022] [Figure 1] This is a schematic plan view showing an embodiment of a circulating non-ferrous metal melting furnace according to the present invention. [Figure 2] This is a schematic plan view showing another embodiment of a circulating non-ferrous metal melting furnace according to the present invention. [Figure 3] This is a schematic plan view showing a conventional circulating non-ferrous metal melting furnace. [Figure 4] This is a schematic plan view showing a circulating non-ferrous metal melting furnace according to another conventional example. [Modes for carrying out the invention]

[0023] A circulating non-ferrous metal melting furnace 1 according to an embodiment of the present invention will be described with reference to the drawings.

[0024] As shown in Figure 1, the circulating non-ferrous metal melting furnace 1 according to this embodiment melts and raises the temperature of non-ferrous metal materials by circulating molten metal and immersing an immersion-type electric heater in the molten metal, with the portion of the heater excluding its upper end submerged in the molten metal, and utilizing the heat generated. The furnace comprises a furnace body 10, rotating blades 20, a first electric heater 30, and a second electric heater 40.

[0025] The furnace body 10 has a roughly elliptical shape in plan view, with its outer shell formed by the furnace wall 10a, and includes an inlet 11 for non-ferrous metal materials, a first heating chamber 12, a second heating chamber 13, and a tapping chamber 14 from which molten metal can be removed. The plan view of the furnace body 10 can also be circular, rectangular, or square.

[0026] The rotating blades 20 are located in the center of the heating chambers 12 and 13 to circulate the molten metal. The first heating chamber (12) is located in the flow path from the inlet (11) to the outlet chamber (14) on the right half side around the rotating blades (20). The first heating chamber 12 is located on the right half side of the rotating blade 20 (the lower side in Figure 1) in the flow path from the inlet 11 to the outlet chamber 14, and the second heating chamber 13 is located on the left half side of the rotating blade 20 (the upper side in Figure 1) in the flow path from the outlet chamber 14 to the inlet 11. The input port 11 is located upstream of the first heating chamber 12. The first heating chamber 12 is connected to the input port 11 and receives non-ferrous metal materials introduced from the input port 11. As a result, the molten metal flows in a circular motion, starting from the inlet 11, passing through the first heating chamber 12 to the outlet chamber 14, and then returning to the inlet 11 side through the second heating chamber 13.

[0027] The hot water outlet chamber 14 is provided so as to be connected to the downstream side of the first heating chamber 12. This molten metal outlet chamber 14 is equipped with a mechanism (not shown) for removing the received molten metal to the outside.

[0028] The first electric heater 30 is installed in the first heating chamber 12 and heats the molten metal to a predetermined first temperature. The number of first electric heaters 30 is not limited. The second electric heater 40 is installed in the second heating chamber 13 and raises the molten metal, which has been heated to the first temperature in the first heating chamber 12, to a second temperature that exceeds the first temperature. The number of second electric heaters 40 is not limited. Furthermore, thermometers, which are thermocouple-type sensors (not shown), are installed in the first heating chamber 12, the second heating chamber 13, and the molten metal outlet chamber 14 to measure the temperature of the molten metal.

[0029] In this embodiment, the non-ferrous metal is an aluminum alloy. The first temperature is set to 650°C to 720°C, which is suitable for casting molten aluminum alloy products. The second temperature is set to 690°C to 750°C, and is set to efficiently melt and heat up the non-ferrous metal introduced from the inlet 11 in a short time by utilizing the heat of the molten metal, which is about 5°C higher than the first temperature. The first and second temperatures can be varied depending on the type of non-ferrous metal being melted and heated.

[0030] In the circulating non-ferrous metal melting furnace 1 configured in this way, which melts non-ferrous metal materials using electric heaters 30 and 40, a rotating vane 20 for circulating molten metal is provided in the center of the heating chambers 12 and 13. The molten metal flows around the rotating vane 20 in a circular motion, dividing into two paths: one that flows from the inlet 11 side through the first heating chamber 12 to the outlet chamber 14 side on the right half, and another that flows from the outlet chamber 14 side through the second heating chamber 13 to the inlet 11 side on the left half. According to this, as shown in the conventional example, there is no need to provide an intermediate wall in the furnace body, and a circulation pump is also unnecessary. Only the rotating blades 20 need to be provided, so the structure of the circulating non-ferrous metal melting furnace can be simplified, and there is no particular increase in cost. Furthermore, by making the molten metal flow in a circular motion, a circulating non-ferrous metal melting furnace can be obtained that allows for a smoother flow of the molten metal and more efficient melting and heating.

[0031] Furthermore, the heating chambers 12 and 13 consist of a first heating chamber 12 and a second heating chamber 13 arranged around the rotating blades 20. The first heating chamber 12 and the second heating chamber 13 are each equipped with a first electric heater 30 that raises the temperature to a predetermined first temperature and a second electric heater 40 that raises the temperature to a second temperature exceeding the first temperature. The molten metal heated to the second temperature in the second heating chamber 13 is circulated back to the first heating chamber 12, and its heat is transferred to the non-ferrous metal material introduced from the inlet 11. This allows for the efficient melting and heating of the non-ferrous metal material in a short amount of time.

[0032] In Figure 1, the rotating blades 20 are provided in the center of the furnace body 10, but as shown in Figure 2, the shape of the furnace body 10 itself can also be made into a donut shape in plan view by providing a space 60 in the center. The furnace body 10, including the furnace wall 10a, may be elliptical or circular in shape.

[0033] In this case, a circulation pump 70 is provided in the second heating chamber 13 to circulate the molten metal along the circulation path. The location and number of the circulation pumps 70 are not limited. Therefore, they can be installed in the first heating chamber 12, or they can be installed in both the first heating chamber 12 and the second heating chamber 13.

[0034] According to this method, by making the molten metal flow in a circular motion, the flow of the molten metal becomes smoother, allowing for more efficient dissolution and heating. In particular, since it only requires making the shape of the furnace body itself a donut shape in plan view, the structure of the circulating non-ferrous metal melting furnace can be simplified without increasing costs.

[0035] In the above embodiments of the present invention, aluminum alloys are used for melting and heating, but other non-ferrous alloys can also be used. Furthermore, the first and second temperatures can be appropriately changed depending on the non-ferrous metal being targeted. [Explanation of Symbols]

[0036] 1 Circulating non-ferrous metal melting furnace 10 Furnace body 10a Furnace wall 11 Inlet 12 First Temperature-Boosting Chamber 13. Second Temperature-Boosting Chamber 14 Hot spring room 15 Intermediate wall 18 Channel 20 rotating blades 30-inch Daiichi Electric Heater 40 Second Electric Heater 50 Circulating non-ferrous metal melting furnace 51 Melting chamber 52 Warming room 53 Debris Removal Room 54 Sedation Room 55 Hot spring room 56 Electric heater 60 space 70 Circulation pump 101 Circulating non-ferrous metal melting furnace 110 Furnace body 110a Furnace wall 111 Inlet 112 First Temperature-Boosting Room 113 Second Temperature-Boosting Room 114 Hot Spring Room 115 Intermediate wall 117 Bulkhead 117a Gap passage 120 Circulation pump 130 Daiichi Electric Heater 140 Second Electric Heater

Claims

1. A circulating non-ferrous metal melting furnace that melts non-ferrous metal materials using an immersion-type electric heater, A furnace body having an inlet for non-ferrous metal material, a heating chamber communicating with the inlet, and a tapping chamber communicating with the heating chamber, which receives a portion of the molten metal heated to a predetermined temperature in the heating chamber and from which the molten metal can be removed. A rotating vane for circulating molten metal is provided in the center of the aforementioned heating chamber, A non-ferrous metal melting furnace, characterized by being provided in the aforementioned heating chamber and comprising a plurality of electric heaters for raising the temperature of molten metal to a predetermined temperature.

2. The heating chamber consists of a first heating chamber provided in the flow path from the inlet side to the outlet side on the right half side around the rotating blade, and a second heating chamber provided in the flow path from the outlet side to the inlet side on the left half side around the rotating blade, The electric heaters consist of a plurality of first electric heaters provided in the first heating chamber to raise the molten metal to a predetermined first temperature, and a plurality of second electric heaters provided in the second heating chamber to raise the molten metal, which has been heated to the first temperature in the first heating chamber, to a second temperature exceeding the first temperature. The non-ferrous metal melting furnace according to claim 1, characterized in that the molten metal heated to the second temperature in the second heating chamber is circulated to the first heating chamber, and the heat is supplied to the non-ferrous metal material introduced from the inlet.

3. A circulating non-ferrous metal melting furnace that melts non-ferrous metal materials using an immersion-type electric heater, The furnace body has an inlet for the non-ferrous metal material, a heating chamber communicating with the inlet, and a tapping chamber communicating with the heating chamber that can receive a portion of the molten metal heated to a predetermined temperature in the heating chamber and from which the molten metal can be removed, and has a space in the center and is donut-shaped in plan view, A circulation pump is provided in the aforementioned heating chamber for circulating the molten metal, A non-ferrous metal melting furnace, characterized by being provided in the aforementioned heating chamber and comprising a plurality of electric heaters for raising the temperature of molten metal to a predetermined temperature.

4. The heating chamber consists of a first heating chamber provided in the flow path from the inlet side to the outlet side on the right half of the space, and a second heating chamber provided in the flow path from the outlet side to the inlet side on the left half of the space, The electric heaters consist of a plurality of first electric heaters provided in the first heating chamber to raise the molten metal to a predetermined first temperature, and a plurality of second electric heaters provided in the second heating chamber to raise the molten metal, which has been heated to the first temperature in the first heating chamber, to a second temperature exceeding the first temperature. The non-ferrous metal melting furnace according to claim 3, characterized in that the molten metal heated to the second temperature in the second heating chamber is circulated to the first heating chamber, and the heat is supplied to the non-ferrous metal material introduced from the inlet.

5. The circulating non-ferrous metal melting furnace according to claim 1 or 3, characterized in that the non-ferrous metal material is aluminum or an aluminum alloy.

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