JPH03199886A - Detachable and replaceable pouring furnace for aluminum ingot rapid melting device - Google Patents

Abstract

PURPOSE:To obtain a pouring furnace, detachable and replaceable easily, by a method wherein molten metal, leaked out of a clearance between contacting parts, is solidified by cooling effect by an annular water cooling tube and heat transfer plates which is in contact with the annular cooling water tube, to form a sealing and connecting layer readily separated comparatively. CONSTITUTION:During the operation of a rapid melting device, molten metal in a retaining furnace 13 is communicated with the molten metal in a pouring furnace 12 through the upper opening of the pouring furnace 12, however, one part of the molten metal is leaked by a small amount through spaces between the upper side wall of the pouring furnace 12 and the opening 13a of the retaining furnace 13 or a gap between the bottom wall of the retaining furnace 13 and the upper surface of the flange 15 of the same and invades into an annular gap 18. In this case, a water cooled copper tube 17 and a heat transfer plate 16, contacted closely with the copper tube 17, are cooled sufficiently by cooling water and, therefore, the molten metal, invaded into the annular gap 18, is solidified at once and fills the annular gap 18 whereby a seal layer is formed and the leakage of the molten metal to the outside of the system is prevented. When the pouring furnace 12 is to be replaced due to the clogging of sludge or the breakage of the same, a driver or a chissel is abutted slightly against the upper wall of the flange 15 and is knocked lightly whereby the pouring furnace. 12 can be extracted out of the retaining furnace 13 to replace the same.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a rapid melting device for aluminum or aluminum alloy (hereinafter referred to as aluminum-based metal) ingots, and more specifically, to a device for rapidly melting aluminum or aluminum alloy (hereinafter referred to as aluminum-based metal) ingots, and more specifically, for die-casting molten aluminum-based metal. When molding by casting into parts for machines, electrical equipment, etc., aluminum-based metal ingots (hereinafter abbreviated as aluminum ingots) are formed immediately before the pouring slot of the die of each die-casting machine or the pouring port of other casting equipment. Using the so-called material insertion melting method, in which about 1 to 2 pieces of molten metal are sequentially inserted and melted directly by induction heating, etc., they are sequentially melted from the surface and flowed down as droplets into a heating and holding furnace to raise and hold the temperature of the molten metal. In addition, in a rapid melting device that uses an electromagnetic pump to pour the metal into the pouring furnace, the pouring furnace, which is prone to damage due to slag adhering to it, can be easily removed and replaced from the heating and holding furnace. This invention relates to a pouring furnace with a removable and replaceable aluminum ingot rapid melting device.

[Prior Art] Aluminum has the characteristics of low specific gravity and low melting point when used as structural members for general machinery, special machinery, vehicles, electrical equipment, etc., and if it is made into an alloy, it can be made to have considerable strength. It is widely used as wrought materials and cast products because of its ability to

Casting products made using the die-casting method use a die-casting machine (also called a die-casting machine) to repeatedly inject molten metal into a mold called a die under high pressure and at high speed, making it possible to create precision cast products. Therefore, demand has been increasing in recent years as it meets the requirements for dimensional accuracy and productivity.

Unlike melting equipment commonly used in many casting machines in foundries, there is no need to maintain high-temperature operation for long periods of time, such as melting furnaces and holding furnaces that supply molten metal. In order to increase work efficiency and improve safety by eliminating processes such as transporting, storing and pumping out aluminum ingots, the inventor of the present invention has developed an aluminum ingot that is placed in the die slot of individual die casting machines or immediately before the pouring port of other casting machines. We have developed various methods for rapidly melting waste materials based on the concept of directly melting the material, raising the temperature to a predetermined pouring temperature, and then pouring the metal into the gui.

A method in which the molten metal is sequentially melted from the surface of the aluminum ingot using the material insertion melting method, and the molten metal is allowed to flow down into a heating and holding furnace as droplets, where the temperature is raised and held, and then the molten metal is allowed to flow down into the pouring furnace for pouring. This is a so-called electromagnetic pump type rapid melting device that uses an electromagnetic pump to raise the temperature by holding the molten metal in a holding furnace and pouring furnace against gravity. The inserted aluminum ingot is melted by induction heating in the melting furnace and guided as droplets to the heating and holding furnace.

In the temperature raising/holding process and the subsequent pouring process, the steps shown in Figure 2 (A
), the molten metal, which is kept in a continuous state in the heating/holding furnace 23 and the pouring furnace 22, is pumped out against the gravity applied to the molten metal by an electromagnetic pump 21 installed around the outer periphery of the pouring furnace 22. The temperature raising/holding furnace 23 is made such that hot water cannot be discharged from the sprue 22a.
By holding the molten metal in both the molten metal and the pouring furnace 22, it is possible to heat the molten metal and raise the temperature. Once the temperature reaches a predetermined temperature, the upward thrust that resists the gravity of the electromagnetic pump 21 is released, or a downward thrust is added. The hot water is then tapped out from the hot water outlet 22a and poured into a die-casting machine or the like.

In addition, in order to ensure that the magnetic flux from the electromagnetic pump 21 penetrates the wall of the pouring furnace 22 at almost right angles and effectively interlinks with the molten aluminum in the pouring furnace 22, the axial center of the pouring furnace 22 is A yoke 24 made of cast iron or the like is provided upright in the center along the line.

[Problems to be Solved by the Invention] By the way, the gap between the yoke 24 and the furnace wall of the pouring furnace 22 is quite narrow, about 3 to 5IIIffi, and the slag flowing into the pouring furnace 22 has a high viscosity and is fluid. Since the slag in the pouring furnace 22 is poured through the narrow gap between the furnace wall and the yoke 24, it adheres to the gap and gradually becomes difficult to remove. For this reason, the pouring furnace 22 breaks down much more frequently than the heating/holding furnace 223.

In order to solve this problem, as shown in Figure 2 (Bl),
The pouring furnace 22b is molded separately from the heating/holding furnace 23b, and male and female tapered conical surfaces 26- that engage with each other are formed between the two.
27 is connected by a spliced joint, and the cement for fireproof material 2
A removable pouring furnace with 8 joints was used on a trial basis.

However, in this pouring furnace, the tapered conical surfaces 26-27
In order to seal the leakage of molten metal, it is essential to use cement 28 for refractory materials.If you do this, the bond will be strong, making it difficult to attach or remove, and if you try to remove it, one or both of them will be damaged. The furnace body was damaged and the expected results were not obtained.

Therefore, the present invention aims to provide a pouring furnace that can be easily attached and detached.6 [Means for Solving the Problems] In order to achieve the above object, the present invention provides (a) a pouring furnace that: The upper end of the cylindrical shape is inserted as it is into the circular opening made in the bottom of the heating and holding furnace, and the thickness of the bottom wall of the heating and holding furnace is at least as large as that from the top end of the pouring furnace with (b). A flange is provided that protrudes radially outward from a lower position that is longer than the flange, and the upper surface of this flange serves as a stopper when the upper end is inserted into the opening of the heating/holding furnace, and also has a contact area with the outer wall of the furnace bottom. (c) A thermally conductive heat exchanger plate is coaxially fitted closely to the lower surface of this flange, and (d) On this heat exchanger plate, radial direction from the outside of the flange is applied. An annular water-cooled tube having approximately the same thickness as the flange portion is placed concentrically between the bottom of the heating and holding furnace and the top surface of the heat exchanger plate at a position that maintains a certain distance between the two. (e) an electromagnetic pump is arranged on the outer periphery of the pouring furnace below the flange portion to form a substantial pouring furnace body; (f) an outer peripheral surface of the flange portion and an inner periphery of the annular water cooling pipe; The annular gap between the surface and the surface is used as a sealing chamber, and the molten metal that leaks from the contact parts of these related members and flows into this chamber is solidified by the cooling effect of the annular water-cooled pipe and the heat exchanger plate in contact with it. The problem was solved by forming a seal layer that completely seals any leaks of molten metal, but which can be peeled off even with a weak force when disassembled for replacement.

1 Effect] There is inevitably some space between the bottom opening of the heating/holding furnace and the upper end of the pouring furnace, and between the top surface of the flange of the pouring furnace and the lower surface of the bottom wall of the heating/holding furnace. A gap remains, and the molten aluminum in the heating and holding furnace infiltrates into the sealing chamber through this gap, but the heat exchanger plate, which forms the floor of the sealing chamber, is sufficiently cooled by the annular water-cooled pipe, so the aluminum melt inside the sealing chamber The infiltrated molten metal solidifies inside the sealing chamber to form a sealing layer.

Therefore, the molten metal will not flow out from the sealing chamber below the flange of the pouring furnace through the gap between the lower surface of the flange and the heat exchanger plate, and after the solidified molten metal fills the sealing chamber. , the molten metal will no longer infiltrate into the sealing chamber, maintaining its function as a sealing chamber.

Aluminum and its alloys have a relatively low solidification temperature of around 660°C, so they are sufficiently cooled by an annular water-cooled tube and solidify in a short time, so they form an alloy layer with heat transfer plates such as copper to form a strong bond. Not at all.

Therefore, when it becomes necessary to replace it due to slag adhesion inside the pouring furnace, it can be easily removed and replaced by applying a relatively light force.

[Embodiment] A preferred embodiment of a removable and replaceable pouring furnace according to the present invention will be described with reference to FIG. In addition, in this figure, the second
The same reference numerals as in FIG. 2(A) indicate the same configuration as in FIG. 2(A).

In FIG. 1, 13 heats the molten metal to a predetermined temperature,
Temperature raising/holding furnace (hereinafter referred to as "temperature raising/holding furnace") that holds the molten metal until it is poured.

A circular opening 13a is formed in the bottom of the furnace, into which a hollow cylindrical portion at the tip of the pouring furnace, which will be described later, is inserted. 12 is a pouring furnace having a tap hole 12b at the lower part of its side wall, and the upper end insertion part 12a including the upper end thereof is connected to the holding furnace 1.
It passes through the circular opening 13a of No. 3 and is inserted into the holding furnace 13. Further, a flange 15 protrudes radially outward from the side wall of the holding furnace 13 at a position lowered from the upper end of the pouring furnace 12 by a distance slightly longer than the thickness of the bottom wall of the holding furnace 13. Reference numeral 16 denotes a heat transfer plate that is fitted onto the outside of the pouring furnace 12 in contact with the lower surface of the flange 15, and is made of a copper-based material with good thermal conductivity, and extends in the radial direction to the side wall of the holding furnace 13. There is. 17 is a water-cooled steel pipe made of a hollow rectangular pipe having the same height as the thickness of the flange 15 and a square cross section, and is connected to the holding furnace 1.
3 and concentrically and annularly arranged radially outward of the flange 15 along the lower side wall of the flange 15. And this water-cooled copper pipe 17
A water supply pipe 19a and a drain pipe 19b are connected to circulate cooling water. In addition, the lower surface of the bottom wall of the holding furnace 13 and the heat exchanger plate 16
An annular gap 18 is defined by a total of four surfaces: between these two surfaces, and between the outer surface of the flange 15 and the inner surface of the water-cooled copper tube 17.

The flange 15 may be formed integrally with the side wall of the holding furnace 13, or may be formed into a ring shape separately from a refractory material and fitted onto the outside.

Next, the operation of this device will be explained.

While the rapid melting device is in operation, the molten metal in the holding furnace 13 and the pouring furnace 12 communicate through the upper opening of the pouring furnace 12, but a portion of the molten metal is connected to the upper side wall of the pouring furnace 12. It leaks little by little from the gap between the opening 13a of the holding furnace 13 and the top surface of the flange 15 and the bottom wall of the holding furnace 13 and enters the annular gap 18. Since the heat exchanger plate 16 is sufficiently cooled by cooling water, the molten metal that has entered the annular gap 18 solidifies on the spot and gradually fills the annular gap 18 to form a sealing layer, and the molten metal enters the annular gap 18. Prevent further leakage to the outside.

If you want to replace the pouring furnace 12 due to blockage or damage, you can take out the pouring furnace 12 from the holding furnace 13 and replace it by tapping the clay wall of the flange 15 with a screwdriver, chisel, etc. I can do it.

Note that the surface of the heat exchanger plate 16 should be finished smooth. It is also easier to separate it from solidified aluminum.

If necessary, the section of the water-cooled copper tube 17 with the water supply turned off is heated with a burner or the like to melt or soften the solidified aluminum, making extraction and replacement easier. A flange is provided slightly below the tip of the pouring furnace so that the tip of the pouring furnace above the flange is removably inserted into an opening in the center of the bottom wall of the holding furnace.

On the other hand, a heat transfer plate is provided on the bottom surface of the flange, the flange is sandwiched between the bottom wall of the holding furnace and the heat transfer plate, and a water-cooled steel pipe is provided radially outward of the flange to cool the molten metal leaking from the gap between these members. The relatively simple structure of solidifying and forming a sill layer completely prevents the molten metal from leaking through the gaps, making it extremely effective and contributing to industry in making the pouring furnace removable and replaceable. It's a huge amount.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an embodiment of a removable and replaceable pouring furnace according to the present invention, and FIG.
FIG. 2B is a partial side sectional view of the vicinity of the connecting portion of the removable and replaceable pouring furnace in the prototype stage. Reference numeral 12 in the drawing: pouring furnace, 13: holding furnace, 15: flange, 17: water-cooled steel pipe, 19a: water supply pipe, 21: electromagnetic pump. 2a 3a 16 : 18 = 9b

Claims (1)

[Claims] 1. When pouring molten aluminum-based metal containing aluminum and its alloys into a casting machine such as a die-casting machine,
A small number of aluminum ingots with components corresponding to the molten metal are successively supplied as cold material at a position close to the casting machine, melted to form molten metal, and heated and held in a heating/holding furnace to form a pouring furnace. In a rapid melting device for supplying cold material to an aluminum ingot, the melt is poured into a pouring port of casting equipment such as a die-casting machine using an electromagnetic pump. The upper end insertion part is inserted and connected to the spigot joint system, and the upper end extends in the radial direction following this upper end insertion part, and its upper surface serves as a stopper when inserting the upper end insertion part, and also serves as a stopper when inserting the upper end insertion part. A pouring furnace body consisting of a flange portion that increases the contact area with the outer wall of the bottom of the holding furnace, and a hollow cylindrical portion below the flange portion; Coaxially inserted into a gap formed between a thermally conductive heat exchanger plate fitted externally and the bottom of the heating/holding furnace and the top surface of the heat exchanger plate with the flange section in between. The molten metal leaking from the gap between the contact area between the annular water-cooled pipe, the opening in the bottom of the heating/holding furnace, the upper end insertion part, the flange part, the heat exchanger plate, and the annular water-cooled pipe is A removable and replaceable aluminum ingot rapid melting device comprising: a seal/bonding layer that is solidified by the cooling effect of an annular water-cooled pipe and the heat exchanger plate in contact therewith and is relatively easily peeled off. Pouring furnace. 2. In the removable and replaceable pouring furnace according to claim 1,
Both the heat exchanger plate and the annular water-cooled tube are made of copper or a copper alloy, and the molten metal that enters between the radially outer end of the flange portion and the annular water-cooled tube is cooled and solidified to prevent the molten metal from leaking to the outside. A removable and replaceable pouring furnace for an aluminum ingot rapid melting device, characterized in that a space is formed that is sufficient to form a sealing layer that prevents the melting of aluminum ingots.