JPH0791844A - Metal melting method and melting furnace - Google Patents

Abstract

PURPOSE:To efficiently melt without mixing oxide even if there is a relatively small matter such as a return material, etc., and to regenerate an ingot or use as molten metal for casting as it is. CONSTITUTION:A heating vessel 20 having an outlet 21 at a lower part is installed in a furnace chamber 11 having a melting burner 13, a material M to be melted is introduced into the vessel, heated, melted and discharged from the outlet into the chamber and melted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
In particular, it relates to a metal melting method and a furnace most suitable for melting a return material of a light alloy casting such as aluminum or zinc.

[0002]

2. Description of the Related Art For example, when a return material (a sprue, a runner, a gate, etc.) of a light alloy casting such as aluminum or zinc is melted and regenerated, the return material is put into a crucible and heated and melted. However, since the return materials such as sprue, runners, and gates are relatively fine and small, they may float on the surface of the crucible during melting, and the surface area of the material to be melted is large, so many oxides are generated, There is a problem in that the defects are frequently generated due to the inclusion of the oxide and the yield is low. Further, when such a relatively fine and small return material is melted by an open flame, there is a problem that the oxidation is intense and the metal loss increases.

Since it has been difficult for a casting maker to solve such a problem conventionally, it is the actual situation that the ingot recycling maker is requested to process the return material. Therefore, the cost of recycling the return material has to be high.

[0004]

SUMMARY OF THE INVENTION The present invention has been proposed in view of such a situation, and even if a return material or the like is relatively fine and small, it does not involve an oxide, It is an object of the present invention to provide a novel metal melting method and a melting furnace therefor, which can be efficiently melted and, if necessary, can be regenerated into an ingot or can be directly used as a molten metal for casting.

[0005]

That is, in the metal melting method according to the present invention, a heating container having an outlet in the lower part is installed in a furnace chamber having a melting burner, and a material to be melted is introduced into the heating container. It is characterized in that it is heated to melt and flow out from the lower outlet into the furnace chamber for melting.

Further, the structure of the metal melting furnace of the present invention is provided with a furnace chamber having a melting burner, a heating container installed in the furnace chamber and having an outlet in the lower part, and communicating with the furnace chamber. It is characterized by comprising a molten metal pouring part.

Further, the structure of the improved furnace of the melting furnace includes a furnace chamber space having a melting burner, a heating container installed in the furnace chamber space and having an outlet in a lower portion thereof, and at least the bottom of the furnace chamber. And a molten metal pouring part provided in communication with the molten metal holding part.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 is a central longitudinal sectional view of a metal melting furnace showing a first embodiment of the present invention, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG. 3 is a metal melting furnace showing a different example of a heating container. Central longitudinal sectional view, FIG. 4 is a central longitudinal sectional view of a metal melting furnace showing a second embodiment of the present invention, FIG. 5 is a sectional view taken along line 5-5 of FIG. 4,
6 is a central longitudinal sectional view of a metal melting furnace showing a third embodiment of the present invention, FIG. 7 is a sectional view taken along line 7-7 of FIG. 6, and FIG. 8 is a third embodiment showing a different example of a heating container. FIG. 3 is a central longitudinal sectional view of the metal melting furnace of FIG.

First, the first embodiment will be described together with the method of the present invention. 1 and 2 show a metal melting furnace 10 according to a first embodiment of the present invention. Reference numeral 11 is a furnace chamber, and 11 is a furnace chamber.
B is the bottom of the furnace chamber, 12 is the furnace body, 13 is the melting burner, 14
Is a chimney (exhaust part), 15 is an inspection port, 16 is its door, 20
Is a heating container, 21 is an outlet, 25 is a molten metal pouring part, 26
Is a molten metal spout, 27 is a molten metal receiving part such as an ingot mold,
M is a return material such as a sprue, a runner, and a gate, and other materials to be melted.

The furnace body 12 is constructed so that the furnace chamber 11 having a predetermined shape is formed of a known refractory material. In the embodiment, a cylindrical shape is formed so that a furnace chamber 11 having a circular cross section is formed as shown in FIG. A melting burner 13 is disposed below the furnace chamber 11, and a chimney is provided above the furnace body 12 adjacent to the melting burner 13 so that combustion gas generated by the burner circulates in the circular furnace chamber 11 and is then exhausted. 14 is provided.

The heating container 20 corresponds to a so-called crucible and is a container for melting the material M to be melted. When the melting temperature is low, cast iron is used, and when the melting temperature is high or when iron content becomes a problem, refractory materials such as graphite and alumina are often used. The heating container 20 has a cylindrical shape having a round bottom portion 22 as shown in the drawing, and is held in the furnace chamber 11 by an appropriate means. In this example, the upper flange portion 23 is attached to the upper portion of the furnace body 12 so that the furnace chamber 11
It is suspended inside. Reference numeral 24 in FIG. 1 is a heat retaining lid of the heating container.

An outlet 21 is provided in the lower part of the heating vessel 20, in the present embodiment, in the bottom 22 and the melting burner 1 is provided.
The melted material M melted by the heating gas No. 3 flows out of the heating container 20 into the furnace chamber 11.

The melted material flowing out into the furnace chamber 11 is further heated by the heating gas of the melting burner 13 to become a molten metal Mm.

A molten metal pouring portion 25 is formed in the furnace chamber 11, and the molten metal Mm is supplied from the molten metal pouring portion 25 to the furnace chamber 1
1 is sent out. In this embodiment, the bottom 11B of the furnace chamber is formed by an inclined surface, and the molten metal spout 26 is formed below the inclined surface.
And a molten metal receiving portion 2 is formed from the molten metal pouring port 26.
Inflow to 7. The molten metal receiving portion 27 is of an ingot type, and the molten metal Mm is cooled here and regenerated into an ingot.

FIG. 3 is a central longitudinal sectional view of a metal melting furnace 10A showing a different example of the heating container in the first embodiment. In this example, a refractory material such as graphite or alumina is used as the heating container 20A, and the heating container 20A is held in the furnace chamber 11 by supporting the bottom portion 22A thereof by the mounting table 19. Since the bottom portion 22A is in contact with the mounting table 19, the outflow port 21A is provided in the lower portion that does not contact the mounting table 19.

Regarding the metal melting furnace 10A in FIG. 3, the same reference numerals as those in FIG. 1 represent the same components. The position of the chimney 14 in FIG. 3 is different from that in FIG.

As described above, the present invention provides the melting burner 1
The heating chamber 20 having the outlet 21 at the bottom is installed in the furnace chamber 11 having the number 3, and the material M to be melted is introduced into the heating chamber 20 to heat the heating chamber 20.
It is melted and flowed out into the furnace chamber 11 and dissolved in the molten metal Mm.

According to such a melting method, the heating container 2
Only the material M to be melted in 0 heated to a fluid (including a semi-molten state) flows out of the lower outlet 21 into the furnace chamber 11 and is further heated in the furnace chamber 11 to be melted. Mm
Is dissolved in. Therefore, the material to be melted (cold material) with a low temperature
Does not come into contact with the molten metal or the light and fine material does not float up in the molten metal, and troubles such as fluctuations in the molten metal temperature or entrapment of oxides are completely eliminated, and a high quality molten metal can be obtained. Further, the material M to be melted in the heating container 20 is gradually heated from the lower part to the upper part, and a preheating effect due to the waste heat is generated, so that the energy can be effectively used.

Other embodiments are illustrated below, based on the above dissolution principle. In the metal melting furnace 30 of the second embodiment shown in FIGS. 4 and 5, the molten metal pumping section 46 is used as the molten metal pouring section 45.
Are formed. That is, as shown in the drawing, the molten metal pouring part 45 is provided in communication with the bottom part 31B of the furnace chamber 31, and is configured as a molten metal pumping part 46 which is pumped to the outside by a not-shown ladle or a pump. 47
Is a lid for heat insulation.

In the type of furnace having the molten metal pumping portion 46 as in this example, the molten metal Mm can be accumulated in the furnace chamber 31 as indicated by the dotted line L in FIG. The accumulation surface L of the accumulated molten metal Mm may be in contact with the bottom portion 42 of the heating container 40.

In the second embodiment, reference numeral 32 is a furnace body, 33 is a melting burner, 34 is a chimney, 35 is an inspection port, 36 is a door, and 41 is an outlet of the heating container 40.
Since the same names as those in the first embodiment are the same components, the description thereof will be omitted.

Further, the metal melting furnace 50 of the third embodiment shown in FIGS. 6 and 7 is an example in which a molten metal holding portion 70 is attached. In the metal melting furnace 50 of the third embodiment, the molten metal Mm is accumulated in the furnace chamber 51, and a holding burner 71 for the accumulated molten metal Mm is provided. That is, as well understood from FIG. 6, the molten metal holding part 7 is communicated with the bottom part 51B of the furnace chamber 51 in which the heating container 60 is installed.
0 is provided, and a holding burner 71 is attached to the upper portion (or side wall portion) of the molten metal holding portion 70. The molten metal holding unit 70 holds and accumulates the melted molten metal Mm at a constant temperature.

Reference numeral 52 in the third embodiment is a furnace body,
53 is a melting burner, 54 is a chimney, 55 is an inspection port, 56
Is a door, and 61 is an outlet of the heating container 60. Since the same names as those in the first embodiment are the same as those in the first embodiment, the description thereof will be omitted.

Regarding the molten metal pouring portion, as is clear from the sectional view of FIG. 7, a molten metal pouring outlet 75 provided in communication with the molten metal holding portion 70 is shown in the upper part of the drawing. Code 7
6 is a tap stopper for opening and closing the spout 75. Further, as shown in the lower part of the figure, the molten metal pouring portion may be configured as a molten metal pumping portion 77. Since the molten metal pumping-out section 77 is the same as that described in the second embodiment of FIG. 4, its description is omitted. The molten metal outlet 75 and the molten metal pumping-out portion 77 may be selectively provided or overlapped.

FIG. 8 is a central longitudinal sectional view of a metal melting furnace 50A showing a different example of the heating container in the third embodiment. In this example, as described above, a refractory material such as graphite or alumina is used as the heating container 60A. Reference numeral 61A is an outlet formed in the heating container 60A, and 69 is a stand for supporting the bottom portion 62A of the heating container 60A.
In addition, regarding the metal melting furnace 60A in FIG. 8, the same reference numerals as those in FIG. 6 represent the same components. In FIG. 8, the position of the molten metal pumping-out portion 77 is different from that in FIG.

[0026]

As shown and described above, according to the present invention, only the material to be melted in the heating container is heated to become a molten fluid (including a semi-molten state) having a high temperature. Since it flows out from the lower outlet into the furnace chamber and is further heated and melted in the furnace chamber, the material to be melted (cold material) with a low temperature may come into contact with the molten metal, or a light and fine material may float in the molten metal. This has the excellent effect that the troubles such as the fluctuation of the melt temperature and the entrainment of oxides caused by this are completely eliminated, and a good quality melt can be obtained.

Further, since the material to be melted accumulated in the heating container is gradually heated from the lower part to the upper part to generate a preheating effect due to the waste heat thereof, efficient melting and effective use of energy can be achieved. Can be planned.

As described above, according to the present invention, even if a return material or the like is relatively fine and small, it can be efficiently dissolved without being entangled with an oxide and, if necessary, can be recycled into an ingot, or It is possible to provide a very useful metal melting method and a melting furnace therefor, which can be directly used for casting as a molten metal.

[Brief description of drawings]

FIG. 1 is a central longitudinal sectional view of a metal melting furnace showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a central longitudinal sectional view of a metal melting furnace showing another example of the heating container.

FIG. 4 is a central longitudinal sectional view of a metal melting furnace showing a second embodiment of the present invention.

5 is a cross-sectional view taken along line 5-5 of FIG.

FIG. 6 is a central longitudinal sectional view of a metal melting furnace showing a third embodiment of the present invention.

7 is a cross-sectional view taken along line 7-7 of FIG.

FIG. 8 is a central longitudinal sectional view of a metal melting furnace of a third embodiment showing a different example of the heating container.

[Explanation of symbols]

 10 Metal Melting Furnace 11 Furnace Chamber 11B Furnace Chamber Bottom 12 Furnace Body 13 Melting Burner 14 Chimney 20 Heating Vessel 21 Outlet 25 Metal Molten Pouring Part 26 Molten Metal Pouring Port 46 Molten Metal Pumping Part 70 Molten Metal Holding Portion 71 Holding Burner 75 Molten Metal Pouring Port 77 Molten metal pumping section M Material to be melted Mm Molten metal

Claims (7)

[Claims] 1. A heating vessel having an outlet in the lower part is installed in a furnace chamber having a melting burner, and a material to be melted is introduced into the heating vessel and heated to melt and flow out from the lower outlet into the furnace chamber. A method for melting a metal, which comprises melting. 2. A furnace chamber having a melting burner, a heating container installed in the furnace chamber and having an outlet at the bottom, and a molten metal pouring portion provided in communication with the furnace chamber. And a metal melting furnace. 3. The metal melting furnace according to claim 1, wherein the molten metal pouring portion is a molten metal pouring outlet provided in communication with the bottom of the furnace chamber. 4. The metal melting furnace according to claim 1, wherein the molten metal pouring section is a molten metal pumping section provided in communication with the bottom of the furnace chamber. 5. A furnace chamber space having a melting burner, a heating container installed in the furnace chamber space and having an outlet in the lower part, and a molten metal holder having a holding burner provided at least in communication with the bottom of the furnace chamber. And a molten metal pouring part provided in communication with the molten metal holding part. 6. The metal melting furnace according to claim 5, wherein the molten metal pouring portion is a molten metal pouring outlet provided in communication with the molten metal holding portion. 7. The metal melting furnace according to claim 5, wherein the molten metal pouring portion is a molten metal pumping portion provided in communication with the molten metal holding portion.