JPH0431515Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a furnace for melting aluminum and other solid metal materials.

[Conventional technology]

Reverberatory furnaces, traditionally known as melting furnaces for aluminum, aluminum alloys, etc., place solid metal materials such as ingots or scraps on the hearth and heat the ceiling of the furnace with combustion flames from burners. However, since only the upper surface of the solid metal material is excessively heated, a large amount of oxides are generated and metal loss is large. In addition, hydrogen gas in the combustion flame is easily absorbed into the molten metal, which causes casting cavities to form. Further, a vertical flue connected to the hot water tank is provided on one side wall of the hot water tank, and an inlet for solid metal material is provided at the upper end opening of the flue, and the solid metal material is introduced into the flue from the inlet. The metal materials that reach the hot water tank are melted in order, and the combustion exhaust gas is discharged through the flue, allowing the solid metal raw materials to be preheated.This type of furnace achieves greater energy savings than the above-mentioned reverberant furnace. However, even in this case, there are problems such as a large amount of metal loss due to oxidation and a large amount of hydrogen gas absorption.

In addition, the small front-hearth type aluminum melting furnace shown in Japanese Utility Model Publication No. 12814/1970 has a sealed reflective part A having a flue k at the top with a damper J that can be opened and closed, as shown in Fig. 6. , a communication port is formed in the continuous part of the forehearth part B which is open at the top, a gate plate m which can be freely moved up and down is attached to this communication port, and the flame can be extended in the direction of the forehearth part B in the reflection part A. Burner n that can be done
and a cover plate O for opening and closing the opening on the forehearth part B. By moving the gate plate m up and down and adjusting the opening degree of the communication port, the forehearth part B is controlled by the flame of the burner N. It allows you to adjust the heating level. However, since this melting furnace directly heats the molten metal with the flame of burner N, it cannot eliminate the disadvantage of a large amount of metal loss due to oxidation, similar to the conventional reverberant furnace described above, and it also requires the use of solid metal material in the fore-furnace part B. When the molten metal is replenished, the temperature of the molten metal in the forehearth section B will inevitably drop rapidly, which will cause the temperature of the molten metal that can be pumped out to fluctuate greatly, which will have a negative impact on the quality of the cast product due to the inconsistent casting temperature. There is a risk.

On the other hand, the melting furnace described in Japanese Patent Publication No. 49-8763, as shown in FIG. A burner d is provided at the upper end opening protruding from the molten metal i of c, and the flame of the burner d is sucked into the container c and heat is transferred from the wall of the container c to heat the molten metal i. A solid metal material f such as an ingot is poured into the bath and melted. g indicates the hot water outlet, and h indicates the flue. This melting furnace is used to melt the molten metal i already melted in the hot water tank b into the solid metal material f put into the hot water tank b.
Solid metal material f
This has the advantage that it can be melted without exposing it to the burner flame, reducing the generation of oxides and improving the yield.

However, in this melting furnace, if a large amount of solid metal material f is charged at once, the temperature of the molten metal i in the bath b decreases, and the required casting temperature cannot be maintained. This may have an adverse effect on quality. For this reason, unless the input amount of the solid metal material f is controlled very strictly, the above-mentioned problem of poor quality may occur.

[Purpose of invention]

Therefore, the present invention aims to solve the various problems of the conventional melting furnace as described above. That is, the objects of the present invention are listed below.

(1) Improve yield by preventing oxidation of metal materials and reducing metal loss.

(2) There is no risk of absorption of hydrogen gas, etc., and the quality is maintained.

(3) To facilitate operations by making it possible to always pump out molten metal at the required temperature without being affected by the amount of solid metal material input.

[Means for achieving the object] In order to achieve the above object, the melting furnace of the present invention partitions the inside of the hot water tank with a partition wall so that a melting chamber and a hot water drawing chamber are formed on both sides of the heat source chamber. Each wall is provided with a communication port through which molten metal can flow, and a refractory bottomed cylinder is inserted into the molten metal in the heat source chamber so that its upper opening protrudes above the surface of the molten metal. The melting chamber is immersed and supported in an upright state, and a burner for blowing combustion fire into the bottomed cylinder is provided at the upper end opening, and the melting chamber is provided with an inlet into which a solid metal material can be introduced, and the melting chamber and the heat source chamber are connected. The heat source chamber side of the partition wall is provided with a gate plate that can adjust the opening amount of the communication port.

[Effect]

Since the molten metal is indirectly heated by transferring heat through the cylindrical wall of the bottomed cylindrical body, there is no oxidation caused by direct contact with the combustion flame. In addition, by moving the gate plate and adjusting the opening amount of the communication port, the transfer of heat between the heat source chamber and the melting chamber can be adjusted. temperature can be maintained, and the dissolution rate of the introduced solid metal material can be adjusted. Then, the molten metal can be supplied to the hot water extraction chamber, whose temperature is adjusted and stabilized by passing through the heat source chamber.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.
A hot water tank 1 is formed on a base using a refractory material mainly composed of alumina. Inside the hot water tank 1, there are partition walls 2 and 6.
Thus, a melting chamber 3 and a hot water extraction chamber 5 are formed on both sides of the heat source chamber 4. Reference numeral 7 denotes an inlet for the solid metal material a formed obliquely above the melting chamber 3. A communication port 8 is provided in the lower part of the partition wall 2. Reference numeral 9 denotes a gate plate on the heat source chamber 4 side of the partition wall 2, which allows the opening amount of the communication port 8 to be adjusted by sliding up and down along the wall surface. The gate plate 9 is made of a sulfur silicate board, and both side edges of the gate plate 9 are slidably fitted into guide grooves 10 formed on both sides of the communication port 8, as shown in FIG. Reference numeral 11 designates a long plate-shaped rod from which the gate plate 9 is suspended, and which is opened in the furnace cover 12 and projects upwardly from the through hole 13, with an engaging pin 14 provided at its upper end. There is. Reference numeral 15 denotes an engagement plate fixed on the hearth 12, and the engagement pins 14 are inserted into the engagement holes arranged vertically in the engagement plate.
By engaging the gate plate 9, the height position of the gate plate 9 is adjusted, and the opening amount of the communication port 8 can be adjusted.

On the other hand, reference numeral 16 denotes a cylinder with a bottom provided in the heat source chamber 4, and a burner 17 is installed at the upper end opening of the cylinder with a plate bottom 16.
is provided, and the combustion flame is injected into an injection pipe 18 hanging down from the center of the bottomed cylinder 16.
The combustion exhaust gas is guided to the exhaust gas pipe 19. The tip of the exhaust gas pipe 19 communicates with the space above the melting chamber 3 through a through hole 22 that penetrates the furnace wall as shown in FIG. Note that a communication port 20 is provided at the lower part of a partition wall 6 that partitions the heat source chamber 4 and the hot water extraction chamber 5, so that the heat source chamber 4 and the hot water extraction chamber 5 are communicated with each other. Further, 21 indicates an insertion port for a thermometer suspended into the heat source chamber 4.

In the melting furnace configured in this manner, molten metal as a source water is prepared in advance in the heat source chamber 4 by heat from the outside or heated by the burner 17, and a solid metal material a such as an aluminum ingot is poured into the melting furnace from the input port 7. It is put into the dissolution chamber 3. There is a communication port 8 in the dissolution chamber 3.
Since the high-temperature molten metal in the heat source chamber 4 is flowing through the melting chamber 3, the solid metal material a in the melting chamber 3 is immersed in the molten metal and melted by receiving the heat. In this case, the heat of the molten metal in the heat source chamber 4 passes through the partition wall 2 into the melting chamber 3 and is also transmitted into the melting chamber 3 through the communication port 8. Therefore, by appropriately adjusting the opening amount of the communication port 8 by moving the gate plate 9 up and down, the dissolution rate of the solid metal material a in the dissolution chamber 3 can be arbitrarily controlled. In this case, if the opening amount is too large, the heat transfer rate will be too fast, and even the molten metal in the heat source chamber 4 may be cooled down when the material is introduced.On the other hand, if the opening amount is too small and the heat transfer is too slow, the heat transfer rate will be too fast. There is a possibility that the dissolution rate of the solid metal material (a) in the container will be slow, resulting in poor productivity. For this purpose, the opening amount of the communication port 8 is adjusted appropriately by the gate plate 9 in consideration of these matters. Note that heat is transferred to the molten metal in the heat source chamber 4 from the entire circumference of the bottomed cylinder 16, and the combustion heat of the fuel in the burner 17 is transferred to the cylindrical wall of the bottomed cylinder 16 and is lost to the molten metal. can be transmitted with high efficiency. Further, the combustion exhaust gas discharged from the exhaust gas pipe 19 fills the space above the melting chamber 3 to suppress heat release from the surface of the molten metal. Moreover, the solid metal material a at the input port can be preheated by the residual heat of this combustion exhaust gas. Furthermore, since the gate plate 9 is provided on the heat source chamber 4 side of the partition wall 2, there is a risk that it will come into contact with the solid metal material a introduced into the melting chamber 3 side, making it difficult to move the gate plate 9 up and down. do not have.

[Effect of idea]

As explained in the embodiments above, the melting furnace of the present invention transfers heat to the cylindrical wall of the bottomed cylindrical body immersed in molten metal in the heat source chamber, thereby eliminating the need to bring the molten metal into direct contact with the combustion flame of the burner. can be heated indirectly, thus preventing oxidation, metal loss, hydrogen gas absorption, etc. In addition, since the hot water extraction chamber is formed on the opposite side of the melting chamber across the heat source chamber, even if a large amount of solid metal material is introduced into the melting chamber at once, the communication port between the melting chamber and the heat source chamber will be closed. By adjusting the opening amount by moving the gate plate, the amount of heat transferred between the two chambers can be adjusted, and the temperature of the molten metal in the heat source chamber and the melting rate of the metal material in the melting chamber can be easily adjusted. Molten metal adjusted to the required temperature can be pumped out. Therefore, the present invention has the practical advantage of making it easier to maintain the quality and temperature of molten metal and to make operations easier.

[Brief explanation of drawings]

The drawings show an embodiment of the melting furnace of the present invention, and FIG. 1 is a plan view, FIG. 2 is a sectional view taken along the line X-X, FIG. 3 is a sectional view taken along the Y-Y line, and FIG. 4 is a sectional view taken along the line Y-Y. is a sectional view taken along the Z-Z line in FIG. 2, and FIGS. 5 and 6 are longitudinal sectional views of a conventional melting furnace. a... Metal material, 1... Hot water tank, 2, 6... Partition wall, 3... Melting chamber, 4... Heat source room, 5... Hot water extraction room, 8, 20... Communication port, 9... Gate Board, 16
...Bottomed cylinder, 17...Burner.

Claims (1)

[Scope of utility model registration request] The interior of the hot water tank 1 is partitioned by partition walls 2 and 6 so that a melting chamber 3 and a hot water extraction chamber 5 are formed on both sides of the heat source chamber 4, and the partition walls 2 and 6 are provided with communication ports 8 through which molten metal can flow. . A burner 17 for supporting and blowing combustion fire into the bottomed cylindrical body 16 is provided in the upper end opening, and the melting chamber 3 is provided with an input port 7 into which solid metal material a can be introduced, and the melting chamber 3 and heat source chamber 4 are provided. A melting furnace characterized in that a gate plate 9 is provided on the heat source chamber 4 side of the partition wall 2 that partitions the melting furnace.